APP Studio Ing's products - APP992 - APP14GE Germanium DOA and other kits

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Hi Pier,
I have a strange issue with the 48V rail of the PSU board.
I can't have more than 30.5v after the regulator.
I use a 2X22v Ac as transformer the jumper is in place.
I have a doubt about the C19/20 values because i found two different values in the shematics. I made my board with the 2010 schematic but some values are changed on the 2012.
I use 100uf/63 like is indicated in the first versoin of your schematic, IC3 is a LM317T.
The other rails work perfectly...

Cyril
 
creal said:
Hi Pier,
I have a strange issue with the 48V rail of the PSU board.
I can't have more than 30.5v after the regulator.
I use a 2X22v Ac as transformer the jumper is in place.
I have a doubt about the C19/20 values because i found two different values in the shematics. I made my board with the 2010 schematic but some values are changed on the 2012.
I use 100uf/63 like is indicated in the first versoin of your schematic, IC3 is a LM317T.
The other rails work perfectly...

Cyril



Hi Cyril,

could you tell me the voltage before the LM317?
100uf/63 caps are very good, many PSU2 works with them in 4 channels preamps.
I have change their values for 8 channels preamps.

thanks
Pier Paolo
 

 
ppa said:
Hi Cyril,

could you tell me the voltage before the LM317?
100uf/63 caps are very good, many PSU2 works with them in 4 channels preamps.
I have change their values for 8 channels preamps.

thanks
Pier Paolo

Hi Pier
The voltage at input of the 317 is 76.5.
 
creal said:
Hi Pier
The voltage at input of the 317 is 76.5.

Hi Cyril,

please check if R6 and R5 are inverted between them


Pier Paolo
 
check please if D5 is inverted too, also put a 15k/22k resistor on +48V out. 
 
ppa said:
check please if D5 is inverted too, also put a 15k/22k resistor on +48V out.

Hi Pier
I got it, i've put a 1k trim instead the 10k.
i definitely need a good pair of glasses.

Thank you for your help

Cyril
 
creal said:
ppa said:
check please if D5 is inverted too, also put a 15k/22k resistor on +48V out.

Hi Pier
I got it, i've put a 1k trim instead the 10k.
i definitely need a good pair of glasses.

Thank you for your help

Cyril

It was a pleasure for me Cyril

The matter is that trimmers have too little labels :)

Pier Paolo


 
Hi

Could someone please point me to the docs (schematic, bom ?) for the PSU2 pcb.

I have some APP Studio pcbs to build!

Thanks
 
ParkOne said:
Hi PPA :)
just send you an email to confirm an order.
Many Thanks,
a+

I have not replayed this post here but transaction is done several days ago (items sold and sent)

;)
 
alexc said:
Hi

Could someone please point me to the docs (schematic, bom ?) for the PSU2 pcb.

I have some APP Studio pcbs to build!

Thanks

OPS... my PM box was full  ;D
 
alexc said:
Hi

Could someone please point me to the docs (schematic, bom ?) for the PSU2 pcb.

I have some APP Studio pcbs to build!

Thanks

docs sent by email  8)
 
Thank you muchly PP

What a nice board set, I must say  (IO pcbs and PSU2 pcb).

These guys will become a nice set of poorman passive eq with makeup.

The hiZ is an elegent bonus.

fabulous.

AC
 
alexc said:
Thank you muchly PP

What a nice board set, I must say  (IO pcbs and PSU2 pcb).

These guys will become a nice set of poorman passive eq with makeup.

The hiZ is an elegent bonus.

fabulous.

AC

thanks for comments
PP
 
fonzobrown said:
Ciao !...at the end here some APP1060's picture ( MA1's rack version) that  i've built

tumblr_mwhcleLYMi1rjxrq5o1_1280.jpg


i've made with AF127 germanium Transistor, Classic api 2503 out transfo and silentarts's Haufe St8456 input transfo

tumblr_mwhcleLYMi1rjxrq5o2_1280.jpg


PierPaolo helped me a lot to fix some component...and at the first listening they seems absolutely fanstastic especially on both elect. bass and guitar and of course voice too

tumblr_mwhcleLYMi1rjxrq5o3_1280.jpg


So happy customer here, really thanks PierPaolo!  :)

the MA1's 1U rack version in the photos was modified for 70 dB of gain with success, very low noise.   
 
Hi Pier Paolo, I'm interested in buying four more APP992 kit DOA's if you have those in store. I also wonder how the DIP model looks like? Plan is to fit them in an Igor Sontec EQ that already have DIP sockets mounted.

Best, Mattias
 
Hi Mattias,

I have just sent the email with the total

regarding the dip version i have just some available

thanks
regs
Pier Paolo 
 
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